Added function get_yday() for obtaining the day of
the year (1 to 366).
Added function get_wday() for obtaining the day of
the week (0 to 6, Sunday to Saturday). The numbering may change prior to
release.
Added functions get_yearweekday(),
get_yearweekday_week() and
get_yearweekday_year() for obtaining year-week-day
representations of Date objects.
Added get_isoweek() and get_isoyear()
functions.
Added get_epiweek() and get_epiyear()
functions.
fymd() for
numeric inputs.